Walter;
The speed should be fine. It will run like a LAN and users should not have a problem. Of course all this is subjective without knowing what the customer is doing and what the expectations are. Have you checked out
http://www.citrix.com/products/If your customer is using WinFrame, so be it. If they are looking to purchase the product, you might first take a look at MetaFrame. WinFrame is limited to NT Server 3.51 while MetaFrame uses NT 4.0 Server and Windows 2000 Server.
My preference is for MetaFrame, but you go with the flow - what ever the customer wants or has.
Tom